Cathead



May ze, 1942. T. E. PURCELL 2,284,540

CATHEAD Filed 001.. 17, 1940 INVENTOR. i BY WM ATTORNEY.

Patented May 26, 1942 UNITED STATES FATNT OifilQE CATHEAD Thomas E.Purcell, Talco, Tex.

Application October 17, 1940, Serial No. 361,547

2 Claims. Y (Cl. 242-117) The present invention is directed to a catheadfor use on drilling rigs.

The principal object of the present invention is the provision of acathead having a removable bearing sleeve which is so formed as to becapable of a special treatment which renders it harder and thereforemore durable.

An additional and important object of the present invention is theprovision in a device of the character described of a pair of flanges toembrace the removable sleeve and a groove in one of said flanges toaccommodate a measuring line.

A further object of the present invention is the provision ol'l a deviceof the character described which is so constructed as to be aircooledwhereby its life is considerably increased.

Further objects and advantages of the present invention will appear fromthe accompanying drawing in which Fig. 1 is a vertical section of oneembodiment f of the present invention;

Fig. 2 is a plan View thereof with parts separated so as to bring outfeatures of construction; and

Fig. 3 is a section along the line A-A of Fig. 2.

Referring to the drawing in detail numeral I designates a shaft which isdriven by a suitable pri-me mover. Keyed to the shaft is a sleeve 2 by akey 3 fitting in a keyway 4 in the shaft and a corresponding keyway inthe sleeve. Communicating with the keyway in the sleeve is a slot 5 inthe sleeve 2. The purpose of the slot is to permit a chisel to bedirected against the key and hammered to effect the removal of the key.This feature is of considerable importance in the structure contemplatedby the present invention since, without the slot, the removal of 'thekey would be a tedious and difficult operation.

Integral with sleeve 2 and forming an extension thereof is a cylinder 6which has formed on its outer surface at the point of its junction withsleeve 2 a radially extending flange 1. Radially extending flange l hasa circumferential groove 8 which affords a guide for a measuring linewhich must be manipulated by the operator of the cathead. The provisionof this groove facilitates the operators work.

The outer face of the flange is provided with circumferentiallongitudinal recess 9 adapted to receive one end of a sleeve l0. Theinnerface of the recess is provided with notches II to accommodatecorresponding teeth I2 on the end of the sleeve whereby relativerotation between the sleeve and the cylinder 6 is prevented.

The portion of the cylinder 6 which is overlaid by the sleeve I0 is cutaway circumferentially and the inner surface of the sleeve itself iscorrespondingly cut away to form an air space I3 between the sleeve andthe cylinder. The cylinder in this area is provided with perforations I4whereby air is circulated between the sleeve and the cylinder duringrotation and the sleeve thereby kept cool. These perforations arepreferably inclined opposite the direction of rotation, as shown in Fig.3. In order to insure a strong current of cooling -air between thesleeve I0 and the cylinder 6 each of the openings I4 is provided with ahood which is welded to the inside of cylinder 6 and has its open endfaced in the direction of rotation of the cylinder. If desired, adjacentsets of hoods may be faced in the opposite direction.

The outer end of cylinder 6 is threaded to receive a ange I5 which bearson its inner face a circumferential, longitudinal recess IBcorresponding with recess 9 in iiange 1, and adapted to accommodate theother end of sleeve I.

The above described embodiment of the present invention offers manydesirable advantages. It is important to note that the sleeve I0 is ofsubstantially uniform outer diameter. This is a necessary featurebecause the heat treatment to which the sleeve is subjected in order toimpart hardness to it is such that, if there are any differences indiameter in the sleeve, cracks would develop. It will be understood thatthe nature of the heat treatment will vary with different kinds of steeland these temperatures for various steels are well known. As can beseen, the sleeve is reversible so that when one side becomes worn theother side can be used, thereby doubling the life of the sleeve. Thesleeve is readily removable and is the only part of the device thatrequires replacement.

It will be apparent that changes may be made in the above describedembodiment of the present invention without departing from the essenceof the invention. Such changes are contemplated within the scope of theappended claims in which it is intended to claim the invention asbroadly as the priord art permits.

Having thus described and claimed the present invention, what is claimedas new and useful and is desired to be secured by Letters Patent is:

1. A cathead comprising an elongated tubular metal body, a keyway on oneend of such metal body adapting it for fixation to a shaft, theremainder of the metal body protruding beyond the end of the shaft toform a hollow cylinder with an open outer end, a slot in the end of saidmetal body overlying said shaft communieating with said keyway, a sleeveremovably mounted on said hollow cylinder having a substantial portionof its length spaced from the outer surface of said cylinder and airinlets provided in said cylinder for admitting air into the spacebetween said cylinder and said sleeve.

2. A cathead comprising an elongated tubular metal body, a keyway on oneend of said metal body adapting it for fixation to a shaft, theremainder of the metal body being adapted to protrude beyond the end ofthe shaft, forming a hollow cylinder with an open outer end, a slotextending through the wall of that end of the metal body overlying saidshaft and communieating with said keyway, a sleeve removably mounted onsaid hollow cylinder having a substantial portion of its length spacedfrom the outer surface of said cylinder, a pair of anges on saidcylinder for holding said sleeve in place and to form a space adapted toreceive a catline, a groove arranged on the periphery of one of saidanges for accommodating a measuring line, and air inlets provided insaid cylinder for admitting air into the space between said cylinder andsaid sleeve.

THOMAS E. PURCELL.

